Field of the Invention
This utility model belongs to the technological sector of domestic and industrial tools and refers specifically to an improvement applied to traditional and electrical pressure cookers equipped with visors on their lids.
Description of the Related Prior art
Pressure cookers are widely used for food cooking because they make this process less expensive and more effective. These tools are provided with lids that seal their interior hermetically, and valves that allow steam to escape, and thus can be used safely.
In general, there are many models of pressure cookers for domestic and industrial use. The commonly known models are pressurized and generally do not have devices that allow the viewing of the food during the cooking process. Thus, at times the cooking process has to be stopped and the pan has to be depressurized to the user check if the cooking is appropriated. In case it is not appropriated, it is necessary to reheat the pan to pressurize it again and resume the cooking process. It is then evident that with the traditional models of pressure cooker it is necessary to spend a reasonable time to check the fluid level and the advancement of the process time, reflecting directly on the cooking process of the food.
Therefore the design of pressure cookers with transparent visors has drawn attention in the household area and there is a race in search of technical solutions for achieving these developments. However, the known proposal do not take into account the dimensional and physical variations—dilatation—of the components when in use. Moreover, it is worth mentioning that these overheated rigid materials are under strong pressure, tension and friction between them.
The European patent EP 0298485 proposes several ways of implementing transparent fixed visors in pressure cookers. That is, these proposed visors are fixed by using metal parts or glued rubbers, bringing risk to its users, because the metals when heated become dilated and may cause cracks and guts between materials and it may cause tension, fatigue and cracks in the glass, resulting in exposure of the physical integrity of the users. Similarly, the Chinese patent CN2464213Y also proposes a way to use a fixed visor in a pressure cooker, but the proposal does not consider the dilations and the stresses of the materials when heated and pressurized, and also does not consider how the seals would be made and how the coupling of the visor with the lid is made, so it is incomplete.
Since these visors are fixed, it is clear the difficulty of access in certain areas of the tool for its proper cleaning. Waste disposal of food and salts impact directly on deteriorating as well as on the emergence of pressure leakage, oxidation and on the emergence of bacteria, reasons that would lead a lay user to attempt to disassemble the visor for cleaning or maintenance. The mistaken reassembly of parts from the pan visor, i.e. if the user accidentally changes the position of some of the parts, may result in a malfunction of the tool or bring potential danger to the user. In general, among the known proposals for pressure cookers equipped with a transparent visor, the ways to facilitate the removal of the visor set for its cleaning were not considered, neither the risks nor the need to avoid its inverted coupling. This demonstrates the fragility of known projects when they are inspected and analyzed in a matter of safety.
In order to provide a viable alternative with total safety and consequently care with the physical integrity of the users, a pressure cooker with a removable visor was developed. As described in the applicant's U.S. parent application Ser. No. 13/496,294 of the same applicant, it is proposed a tool provided with transparent visors on the lid and/or body of the pan. The visor is coupled to the inside of the lid and consists primarily of a part of tempered glass and a part of nontoxic polymeric material (rubber, silicone, etc.) with the aim of proposing a coupling device that can be coupled and removed many times in the hole specially designed for viewing. Thus, in summary, it is proposed a pressure cooker with removable visors. However, it is noteworthy that the embodiments of the coupling sealing material do not have an arrangement that securely meet the fixing of the glass and of the visor itself to the pressure cooker lid.
Based on the above it is clear the impossibility to use these fixed visors in pressure cookers without any risk to the end user.